Allogeneic T cells increase FA transport during GVHD. (A) B6 Ly5.2 (CD45.1⁺) donor T cells were loaded with CellTrace violet and transferred to irradiated B6D2F1 mice as described in “Methods.” Cells were recovered 1, 3, or 7 days after transplantation, stained for CD45.1 and TCR-β, and assessed for BoDipy_C1-C12 uptake. Unmanipulated donor cells (not labeled with CellTrace) from “naïve” mice served as controls. Plots are gated on CD45.1⁺, TCR-β⁺ cells. (B) The percentage of BoDipy^Hi donor T cells (n ≥ 3/group). (C) Cells were preincubated with or without palmitate followed by measurement of BoDipy_C1-C12 uptake as described in “Methods.” (D) Cells were processed as in A, then stained with Vibrant Dye Ruby, and the percentage of cells in G2/S/M phase from either BoDipy^Lo (lower 2 quartiles) or BoDipy^Hi (upper quartile) populations (n = 6 mice/group) was measured. (E) Donor T cells 7 days after BMT were assessed for IFN-γ production, followed by BoDipy_C1-C12 uptake. **P < .004, ***P < .0001; n.s., not significant.